The invention relates to the field of lancing aids for the diagnostic determination of blood parameters. Body fluids are collected and analysed in many fields of medical diagnostics. It is therefore desirable to also enable routine tests to be carried out rapidly and reproducibly outside the laboratory. The testing can be carried out with various body fluids such as, e.g., blood and/or interstitial fluid. These fluids can be analysed for various characteristics. The results of this analysis are important in order to be able to make reliable diagnoses and to carry out therapeutic measures and therapeutic monitoring.
The analysis of body fluids begins with the collection of fluid. One method of collecting body fluid is to generate a minimal wound in the skin of a patient with the aid of a needle, lancet or knife. The body fluid obtained in this process can either be collected in small vessels or directly brought into contact with a test element such as, e.g., a test strip for analysis. Most of these lancing aids require the lancet to be manually inserted into the lancing aid. This handling is very laborious when the lancing aid is used frequently. The storage of lancets in magazines can eliminate this problem but in this case many safety aspects have to be observed. Care should, for example, be taken to safeguard the safety of the patient when the lancing aid is used. Moreover, the system should not become too complex because it would otherwise not be easy to operate by the patient. Another important feature apart from storage in magazines is the possibility of adjusting the lancing depth before the lancing process. This can be ensured by the device as, for example, described in publication WO 2006038044. The adjustment of the lancing depth by the device requires a complicated mechanism because the lancet drive and the lancing depth adjustment control mechanism must be adapted to one another. Alternatively, the lancing depth could also be controlled by the lancets.
Although lancing aids are described in the prior art which have more than one lancet, in these cases it is not possible for the user to influence the lancing depth before lancing. A lancet system is, for example, described in U.S. Pat. No. 4,794,926 in which a plurality of lancets that can be used individually for the lancing process is stored on a base body. However, this system does not offer any possibility for the patient to select the lancing depth before the lancing process.